Minimally invasive surgery is a generic term for operative interventions with minimal trauma. It has always been the objective of operative treatment to bring about rapid recovery with minimal discomfort after the operation. At the start of the 1990s, laparoscopic and endoscopic surgery initially established themselves only as simple operative interventions, but later also established themselves for carrying out complex operations.
Nowadays, a differentiation is made between laparoscopic surgery and endoscopy. In laparoscopic surgery, the same interventions are, for all intents and purposes, made as with open surgical methods. However, the largest difference as compared to conventional interventions is that the area to be operated on is reached by significantly smaller incisions than with the conventional open surgery methods.
In contrast, in endoscopy, a doctor can gain a good view into the natural body cavities and hollow organs of the patient, identify illnesses and possibly also treat them immediately without large-scale surgical intervention. To this end, flexible or rigid endoscopes are used to examine the organs and e.g. look at their mucous membrane. For this purpose, there are also endoscopes with different outer diameters, lengths, biopsy channel diameters and functions. Moreover, so-called interventional endoscopy is no longer used exclusively in diagnosis, but is also frequently used in the treatment of a wide range of illnesses.
Typical applications for laparoscopic surgery and/or interventional endoscopy are, for example, a selective tissue separation by high-frequency (HF) or water jet surgery and haemostasis (coagulation) or vascular sealing by HF forceps or electrodes. Furthermore, surgical forceps are also used for dissection or biopsy removal of tissue, or also only for tissue preparation or fixing.
Endoscopic mucosal resection (EMR), in which tumors with large surface areas in the gastrointestinal tract are removed, is carried out for example, with the help of water jet technology, whereby HF surgery is used for haemostasis (coagulation). In this case, the blood vessels, which were previously separated selectively from the tissue with water jet technology, are securely sealed in a targeted manner with HF forceps.
In water jet surgery, an extremely fine laminary water jet is used which, as it were, pushes apart the tissue and forms an expansion space. Soft tissue can, in principle, be dissected at a low pressure, whereby tissue with high elasticity or large expansion, such as for example, blood vessels, escape the water jet and are thus protected.
In contrast, in HF surgery, electrical energy is converted into heat and is thus able to separate biological tissue and also bring about haemostasis. Therein, it is mainly thermal effects which are utilized. Temperatures of 60° C. to 70° C. in the region around the HF surgery electrode lead to protein coagulation. The term coagulation is used to refer to this process. This “welding effect” can be used, for example, to stop bleeding.
During separation, as a result of a higher current density, temperatures of over 100° C. are achieved such that the fluid evaporates in an explosive manner, the space is enlarged and the cell membrane “bursts.” Further, cells located in the direction of electrode movement follow this effect, as a result of which the desired incision or separation of the tissue is achieved.
In HF surgery, a differentiation is also made between monopolar and bipolar application technology. In the case of monopolar application technology, the flow of current takes place from a HF surgery electrode, through the biological tissue and to a neutral electrode, which is usually positioned on a large surface area on the patient. In contrast to this, in the case of bipolar application technology, the HF current does not flow across the body of the patient to a neutral electrode. In the case of bipolar forceps or clamps, an active electrode and a neutral electrode are arranged directly opposite one another, whereby the HF current only flows from the active electrode to the neutral electrode. This results in very short current paths and defined coagulation regions with a low power requirement.
During an operation (e.g., EMR) various instruments are frequently required for gripping, rinsing, separating and/or coagulating tissue and have to be interchanged correspondingly in the working channels. However, the continuous interchange of instruments requires a lot of time and can significantly extend the length of an operation.
A multifunction device, which comprises for example, an HF manual instrument for bipolar coagulation, cutting and gripping as well as a rinsing tube and suction tube additionally accommodated in a protective tube, is known from DE 42 42 143 C2. The tubes (rinsing, suction) which are accommodated in a protective tube, however, do not enable any selective separation of HF and water jet surgery and require, among other things, additional space since they are attached parallel to the electrodes on the manual instrument.
Furthermore, DE 100 56 238 A1 describes a device with a jaw mechanism for tube shaft instruments for the removal of intracorporal tissue samples which can be sucked away through a tube shaft in the proximal direction. The open jaw passage can additionally be used for rinsing or sucking away or also for the introduction of coagulation electrodes, lenses or other operational probes. However, the instruments and probes used must be correspondingly interchanged during the intervention.
It is therefore desirable to have available a multifunction device for endoscopic surgery which can be universally used and takes up little space.